The conventional state-of-the-art antenna switch consists of a set of series field effect transistors (FETs) and a single antenna bond wire connecting the common node to the antenna. The FET devices are electrically nonlinear and generate harmonic contents. Conventional inductor-capacitor (LC) filters can be used to filter out harmonics, but an LC filter has limitations in a single-ended switch where the on-chip capacitor is susceptible to electrostatic discharge (ESD) damage when one side of the capacitor is grounded.
Accordingly, there is a need to develop a radio frequency antenna switch that rejects harmonic frequencies generated by the switch devices and is not susceptible to electromagnetic discharge damage.